Video signal recording apparatus and video signal regenerating apparatus

ABSTRACT

To a conventional video signal recording apparatus, there are added additional information generating means and data replacement means for replacing data at a specified position in compressed data with additional information generated by the additional information generating means. This enables to provide a video signal recording apparatus and a video signal regenerating apparatus which are able to increase transmissible information content, an image coding apparatus that executes high-efficiency non-linear quantization at a small circuit containing no quantization table and also prevents error propagation; and an image decoding apparatus for regenerating coded data obtained in the image coding apparatus.

FIELD OF THE INVENTION

The present invention relates to a video signal recorder for recordingvideo signals, a video signal regenerator for regenerating the recordedsignals, an Image coding apparatus for compressing and recording imagedata from video signals by coding, and an image decoding apparatus forregenerating the coded and recorded image.

BACKGROUND OF THE INVENTION

Recently there have been developed various video signal recorder thatcode and compress video signals of digital data by a specified mode andperform a digital recording. It is, however, required much expense andlabor for the standardization of compression modes and compressedalgorithm hardware, e.g., LSI. In order to reduce the development costsfor early development, it is preferable to apply a known standard andits corresponding accumulated techniques, a known hardware of compressedalgorithms and the like. Hence there have been developed novel videosignal recorders depending on the purpose.

For example, the mode employing 411 digital video signal in which theratio of luminance signal, chrominance signal and another chrominancesignal is 4:1:1, is widely used in general apparatuses for domestic use.While, depending on the purpose, 422 digital video signal containingmore chrominance signal may be more preferable in terms of image qualityand the like. There have been developed apparatuses that can treat 422digital video signal by applying the standards and hardware ofalgorithms for 411 digital video signal.

FIGS. 13(a) to 13(d) are diagrams illustrating the construction of thesignal. FIG. 13(a) shows 411 digital video signals that is generallyused. FIG. 13(b) shows 422 digital video signal used when high imagequality is required. In Figures, “Y” indicates luminance signal, “V” and“U” indicate chrominance signal.

In order to apply such apparatuses as developed in the standard for 411digital video signal to 422 digital signal, the following processing isperformed. That is, 422 digital video signal as shown in FIG. 13(b) aresplit into 211 digital video signal, which signal are then appended withdummy signal to create pseudo-411 digital signal as shown in FIG. 13(d),followed by necessary processing. The signal shown in FIG. 13(d) has thesame format as that of FIG. 13(a), allowing to apply the apparatus withthe standard for 411 digital video signal. The two split signals are tobe synthesized when recording or regenerating.

A description will be given of a conventional video signal recorder anda video signal regenerator, each treating 422 digital signal asdescribed.

Referring to FIG.12(a), there is shown the construction of theconventional video signal recorder. A video signal splitter 1001 splits422 digital video signal with luminance signal to chrominance signalratio of 4:2:2 into two 211 digital video signals with that ratio of2:1:1, based on a specified split format. A video signal converter 1002adds a specified dummy signal into the luminance signal in the input 211digital video signal to convert it into 411 digital video signal withthe luminance signal to chrominance signal ratio of 4:1:1. Ahigh-efficiency coding apparatus 1003 performs a specifiedhigh-efficiency coding of the input 411 digital video signal to createcompressed data. An error correction coding apparatus 1004 appends aspecified error correction coded data to the compressed data. A recorder1005 records the output of the error correction coding apparatus 1004 ina recording media 1006, e.g., tape media such as VTRs, disk media suchas optical disks. In the recording media 1006, digitized data isrecorded for the retention.

The video signal recorder so constructed will perform the aforesaidcompression, coding and recording as follows. The video signal splitter1001 abolishes, from the input video signal, portions other than asignificant area as a processing object, and then splits 422 digitalvideo signal with the luminance signal to chrominance signal ratio of4:2:2, into two 211 digital video signal with that ratio of 2:1:1, basedon a specified split format. The two split 211 digital video signal areseparately input into either of the two video signal converters 1002.

Each video signal converter 1002 appends a specified dummy signal to theluminance signal in the input 211 digital video signal, to convert itinto 411 digital video signal with the luminance signal to chrominancesignal ratio of 4:1:1. The data of the 211 digital video signal issequenced in this order: luminance signal (Y), luminance signal (Y),chrominance signal (V), and chrominance signal (U), as shown in FIG.13(c). The above data is then converted into 411 digital video signalwith the sequencing of the luminance signal (Y), dummy signal (D), theluminance signal (Y), dummy signal (D), the chrominance signal (V), andthe chrominance signal (U), as shown in FIG. 13(d). All the dummy signal(D) are identical data. Each video signal converter outputs theconverted 411 digital video signal to the high-efficiency coder 1003.

Each coder 1003 performs a high-efficiency coding of the input 411digital video signal by employing a specified high-efficiency coding aalgorithm, and then outputs it as compressed data.

Referring to FIGS. 14(a) and 14(b), the format of the compressed datawill be exemplified. The coder 1003 inherently performs ahigh-efficiency coding of 411 digital video signal by the algorithmutilizing DCT (discrete cosine transform). A DCT block consists of 8×8pixels. A macro block consists of four DCT blocks of luminance signal(Y), one DCT block of chrominance signal (V) and one DCT block ofchrominance signal (U). The compressed data of this macro block issequenced as shown in FIG. 14(a). The sequence of each DCT block isfirst DC components, then additional information data, and ACcomponents.

In this example, since there is employed pseudo-411 digital signal basedon 422 digital signal, the sequence of the DCT block is as shown in FIG.14(b), and that of the block of the dummy signal (D) is first aspecified DC components, then additional data and finally EOB (end ofblock).

Each coder 1003 outputs such compressed data as shown in FIG. 14(b) tothe error correction coder 1004. Each coder 1004 appends errorcorrection codes to the input compressed data by a specified mode toobtain the error correction coded data, and outputs it.

The recorder 1005 records the error correction coded data in a specifiedposition of a specified recording media 1006. Thus, the conventionalvideo signal recorder codes/compresses 422 digital video signal and thenrecords it.

It is noted that the video signal recorder may have two recorders 1005which separately write in the recording media 1006, as shown in FIG.12(a), or may have a synthesizer 1007 that synthesizes two outputresults and then write in the recording media 1006. The operation of thelatter is the same as that of the former, except the synthesize and thewriting.

Referring to FIG. 15, there is shown the construction of a conventionalvideo signal recorder, in which video data as recorded in the abovemanner is regenerated to obtain videos. A recording media 1006 is to berecorded video data (error correction coded data) in the conventionalvideo signal recorder, as previously described. A regenerator 2001regenerates the error correction coded data from the recording media1006. An error correction decoder 2002 performs the error correctionsbased on the error correction codes added in the video signal recorderto obtain compressed data, and then outputs it. A high-efficiencydecoder 2003 performs the reverse conversion of the high-efficiencycoding performed by the video signal recorder to decode digital videosignal. A video signal separator 2004 separates the dummy signal addedin the video signal recorder out of 411 digital video signal (luminancesignal to chrominance signal ratio is 4:1:1) which has been decoded bythe high-efficiency decoder 2003, to output 211 digital video signal(luminance signal to chrominance signal ratio is 2:1:1). A video signalsynthesizer 2005 synthesizes 211 digital video signal output from twovideo signal separators 2004, based on a specified synthetic format,thereby obtaining 422 digital video signal with luminance signal tochrominance signal ratio of 4:2:2.

The video signal regenerator so constructed will regenerate the datarecorded in the recording media as follows.

The regenerator 2001 regenerates the error correction coded datarecorded in a specified position of the recording media 1006. The errorcorrection decoder 2002 performs the error correction based on the errorcorrection codes added in the video signal recorder to output compresseddata. The high-efficiency decoder 2003 decodes the compressed data byperforming the reverse conversion of the high-efficiency coding in thevideo signal recorder, to output it as 411 digital video signal. Thevideo signal separator 2004 separates the dummy signal added by thevideo signal recorder from the 411 digital video signal decoded by thehigh-efficiency decoder 2003, to output the 211 digital video signal.The video signal synthesizer 2005 synthesizes, based on the syntheticformat, the 211 digital video signals as the outputs of the two videosignal separators 2004 to obtain the 422 digital video signal, and thenoutputs it. The separated dummy signal is to be discarded.

As described above, the conventional video signal recording apparatusand video signal regenerating apparatus are for recording andregenerating 422 digital video signal, respectively, according to thestandards and devices basically for 411 digital video signal.

It should be noted that in the conventional video signal recordingapparatus dummy signal is added to the original video signal, while inthe conventional video signal regenerating apparatus the dummy signal isseparated and then discarded. Such useless data treatment in therecording and transmission of video signal will decrease the efficiency.Particularly on recording media, dummy signal requires a storagecapacity like video signal. This will cause disadvantages to theeffective use of recording media.

When obtaining digital data to be treated by computers and the like,based on the video signal of such as TV signal, it is general that imagedata comprising digitized video signal is first obtained, the image datais then compressed and coded, and the obtained data is recorded ortransmitted. The digitized image data is in a sequence of pixel datahaving pixel values indicating luminance and chrominance, and the imagedata is coded by processing to obtain coded image data.

As a general method for compressing/coding image data based on videosignal, there is predictive coding. The predictive coding is a system inwhich a predictive value for an input pixel that is the object of codingis generated, and a difference value between the input pixel and thepredictive value is subjected to non-linear quantization, the obtaineddata is then transmitted. When the image from video signal is treated, apredictive value is obtained by predicting a pixel value at a certainpoint, from its periphery pixels, based on that adjacent parts tends tohave the same or an approximate pixel value indicating luminance andchrominance. The predictive coding has the advantages that the circuitscale for an apparatus is small and the compression rate is low. Whendata rate after compression is high, high-quality image is obtainable.This is the reason why the predictive coding has been widely used.

FIG. 43 is a conceptual diagram explaining the linear processing andnon-linear processing in quantization. Input data has a certain dynamicrange. That is, the input data is represented in the range of d-bit as adynamic range, and, the linear processing is possible. When n-bit outputdata is obtained by quantizing the input data, a suitable number ofquantization representative values are selected, and quantizing valuesare allocated to the representative values. To each input data, there isgiven a quantizing value allocated to a quantization representativevalue that is approximate to the input data. By setting the number ofthe quantization representative values to not more than 2^(n), theoutput data can be treated by n-bit.

As shown in FIG. 43, to set quantization representative values atuniform intervals is linear quantization. When an expected value ispreviously obtained as in the predictive coding, non-linear quantizationin which the quantization representative values are set densely in thevicinity of the expected value, and widely as the distance from theexpected value, and widely as the distance from the expected value isincreased.

In FIG. 43, there is shown a rounding processing of from 3-bit to 2-bit.By setting four (2²) quentization representative values against eight(2³) ones, the output data can be represented by 2-bit.

In the linear processing, the quantizing representative values are set,for example, by selecting every other piece, to assign the quantizingvalue. For input data having the values from 0 to 7, they are replacedwith the adjacent quantizing representative value to give a quantizingvalue assigned to the respective representative value in the followingmanner. For the value of 0 or 1, its quantizing representative value is0, for the value of 2 or 3, its quantizing value is 2, and the like.

In the non-linear processing, when an expected value for the input datais 3, for example, the setting of quantizing values will be set denselyin the vicinity of 3, and roughly as the distance from 3 is increased.As the quantizing width is creased, that is, as the interval of thequantizing representative values is increased, the number of datareplaceable with the quantizing representative value is increased. Thisshows that data of different value tends to be treated equally.Therefore, nearer the vicinity of the expected value, the magnitude ofthe quantizing value reflects more precisely the magnitude of the inputvalue.

The non-linear quantization utilized in the predictive coding isperformed in various systems. Since it is normally difficult to performthe non-linear quantization by such a simple operation as in the linearquantization, that is performed by referring to a table such as a ROMtable. This might increase the circuit scale and the processing costs,resulting in the cost increase and the reduced processing speed.

On the other hand, the predictive coding has the problem thattransmitted data is a difference value between an input value and apredictive value and, when an error of the predictive value occurs, suchan error will be propagated at the regeneration. Thus in order tosuppress such an error propagation within a certain range, there hasbeen employed a method of inserting a PCM value periodically. Thismethod, however, decreases the compression rate and causes theunevenness in image quality, failing to solve the problem.

A method of preventing the error propagation without reduction incompression rate is disclosed, for example, in Japanese PatentApplication No. 60-160599. In this method, among a plurality ofnon-linear quantizing units there is selected one unit whosequantization width in the vicinity of a predictive value is small, toperform the quantization. This method basically utilizes the directquantization of input pixel values, not the quantization of differences.As a result, the predictive value error is hardly propagated. However,the construction provided with a plurality of quantizing units willincrease its circuit scale, leading to the cost increase.

SUMMARY OF THE INVENTION

It is an object of the present invention to provided video signalrecording apparatus and a video signal regenerating apparatus thateffectively utilize recording media and device resource by recordingadditional information in an area where a dummy signal has been recordedin a conventional video signal recording apparatus.

It is a further object of the invention to provide a image codingapparatus that performs non-linear quantization processing at high speedand with a small circuit scale, without ROM tables, and prevents theerror propagation during predictive coding without reduction incompression rate.

It is yet another object of the invention to provide a image decodingapparatus that performs decoding processing at high speed and with asmall circuit scale, without ROM table.

Other objects and advantages of the present invention will becomeapparent from the detailed description given hereinafter; it should beunderstood, however, that the detailed description and specificembodiment are given by way of illustration only, since various changesand modifications within the scope of the invention will become apparentto the those skilled in the art from this detailed description.

According to the aspect the present invention provides a video signalrecording apparatus comprising effective area dividing means thatdivides digital video signal to obtain video signal in a significantarea; video signal adding means for adding additional signal to thevideo signal of the significant area; compression means for creatingcompressed video data by performing a specified high-efficiency codingof the video signal containing the additional signal; additionalinformation generating means for generating additional information; datareplacing means that replaces the compressed video data at a specifiedposition in the compressed data with the additional information; andrecording means for recording the compressed data in specified recordingmedia.

According to another aspect the invention provides a video signalregenerating apparatus comprising means for regenerating compressed datarecorded in a specified recording media, means for decoding thecompressed data, which decoding being the reverse conversion of thespecified high-efficiency coding, to output digital video signal; areadividing means for dividing the digital video signal into a specifiedsignificant area and additional information; video signal arrangingmeans for arranging the significant area in a specified order; and meansfor recognizing the additional information by a specified system.

According to another aspect the invention provides an image codingapparatus comprising predictive value generating means that generates apredictive value for an input pixel value from pixels in the vicinity ofthe input pixel; linear quantizing unit generating means for generatinga linear quantizing unit which has a quantization width of 2^(d−n) ind-bit accuracy, and has linear quantization representative points, thenumber of which is obtained by subtracting a pre-set addition upperlimit from 2^(n); non-linear quantization unit generating means in whichto the quantization representative values of the linear quantizationunit, quantization representative points of not more than the additionupper limit are added in the vicinity of the predictive value togenerate a non-linear quantization unit, whose quantization width in thevicinity of the predictive value is smaller than that of the linearquantization unit; and quantization means for quantizing an input pixelvalue by the non-linear quantization unit to obtain a quantizationvalue.

According to another aspect the invention provides an image decodingapparatus comprising predictive value generating means that generates apredictive value for an input quantization value from pixels in thevicinity of the input quantization value; linear quantizing unitgenerating means for generating a linear quantizing unit which has aquantization width of 2^(d−n) in d-bit accuracy, and has linearquantization representative points, the number of which is obtained bysubtracting a pre-set addition upper limit from 2^(n); non-linearquantization unit generating means in which to the quantizationrepresentative values of the linear quantization unit, quantizationrepresentative points of not more then the addition upper limit areadded in the vicinity of the predictive value to generate a non-linearquantization unit, whose quantization width in the vicinity of thepredictive value is smaller than that of the linear quantization unit;and reverse quantization means that performs the reverse quantization ofthe input quantization value by the non-linear quantization unit toobtain a regenerative value.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1(a) and 1(b) are block diagrams showing a construction of videosignal recording apparatus according to Embodiment 1 and 2,respectively,of the invention.

FIGS. 2(a) to 2(c) are diagrams for explaining video signal utilized inthe video signal recording apparatus of Embodiment 1.

FIGS. 3(a) and 3(b) are diagrams showing a construction of video signalrecording apparatus of Embodiment 3 and 4, respectively, of theinvention.

FIGS. 4(a) and 4(b) are diagrams showing a construction of video signalrecording apparatus of Embodiment 5 and 6, respectively, of theinvention.

FIGS. 5(a) and 5(b) are diagrams for explaining video signal utilized inthe video signal recording apparatus of Embodiment 5.

FIGS. 6(a) and 6(b) are diagrams showing a construction of video signalrecording apparatus of Embodiment 7 and 8, respectively, of theinvention.

FIGS. 7(a) and 7(b) are diagrams for explaining video signal utilized inthe video signal recording apparatus of Embodiment 7.

FIGS. 8(a) and 8(b) are diagrams showing a construction of video signalrecording apparatus of Embodiment 9 and 10, respectively, of theinvention.

FIGS. 9(a) and 9(b) are diagram for explaining video signal utilized inthe video signal recording apparatus of Embodiment 9.

FIGS. 10(a) and 10(b) are diagrams showing a construction of videosignal regenerating apparatus of Embodiment 11 and 12, respectively, ofthe invention.

FIGS. 11(a) and 11(b) are diagrams showing a construction of videosignal regenerating apparatus of Embodiment 13 and 14, respectively, ofthe invention.

FIGS. 12(a) and 12(b) are diagrams showing a construction of aconventional video signal recording apparatus.

FIGS. 13(a) to 13(d) are diagrams for explaining the conversion of videosignal in the conventional video signal recording apparatus.

FIGS. 14(a) and 14(b) are diagrams for explaining video signal utilizedin the conventional video signal recording apparatus.

FIGS. 15(a) and 15(b) are block diagrams showing a construction of aconventional video signal regenerating apparatus.

FIG. 16 is a block diagram showing a construction of a image codingapparatus of Embodiment 15 of the invention.

FIGS. 17(a) to 17(d) are diagrams for explaining the quantization of theimage coding apparatus of Embodiment 15.

FIG. 18 is a block diagram showing a construction of the image decodingapparatus of Embodiment 15.

FIG. 19 is a block diagram showing a construction of an image codingapparatus of Embodiment 16 of the invention.

FIGS. 20(a) to 20(d) are diagrams for explaining the quantization of theimage coding apparatus of Embodiment 16.

FIG. 21 is a block diagram showing a construction of an image decodingapparatus of Embodiment 16.

FIG. 22 is a block diagram showing a construction of an image codingapparatus of Embodiment 17 of the invention.

FIGS. 23(a) to 23(d) are diagrams for explaining the quantization of theimage coding apparatus of Embodiment 17.

FIG. 24 is a flow chart showing a coding algorithm of the image codingapparatus of Embodiment 17.

FIG. 25 is a block diagram showing a construction of an image decodingapparatus of Embodiment 17.

FIG. 26 is a flow chart showing a decoding algorithm of the imagedecoding apparatus of Embodiment 17.

FIG. 27 is a block diagram showing a construction of an image codingapparatus of Embodiment 18 of the invention.

FIG. 28 is a flow chart showing a coding algorithm or the image codingapparatus of Embodiment 18.

FIG. 29 is a block diagram showing a construction of an image decodingapparatus of Embodiment 18.

FIG. 30 is a flow chart showing a decoding algorithm of the imagedecoding apparatus of Embodiment 18.

FIG. 31 is a block diagram showing a construction of an image codingapparatus of Embodiment 19 of the invention.

FIGS. 32(a) to 32(d) are diagram for explaining the quantization of theimage coding apparatus of Embodiment 19.

FIG. 33 is a block diagram showing a construction of an image decodingapparatus of Embodiment 19.

FIG. 34 is a block diagram showing a construction of an image codingapparatus of Embodiment 20 of the invention.

FIG. 35 is a block diagram showing a construction of an image decodingapparatus of Embodiment 20.

FIGS. 36(a) and 36(b) are diagrams for explaining the coding of theImage coding apparatus and the decoding of the image decoding apparatusof Embodiment 20.

FIG. 37 is a block diagram showing a construction of an image codingapparatus of Embodiment 21 of the invention.

FIG. 38 is a block diagram showing a construction of an image codingapparatus of Embodiment 22 of the invention.

FIG. 39 is a flow chart showing a coding algorithm of an image codingapparatus of Embodiment 23 of the invention.

FIG. 40 is a block diagram showing a construction of an image decodingapparatus of Embodiment 24 of the invention.

FIG. 41 is a block diagram showing a construction of an error codeprocessing unit of the image decoding apparatus of Embodiment 24.

FIG. 42 is a block diagram showing a construction of a circuit sharedbetween an image coding apparatus and an image decoding apparatus ofEmbodiment 25 of the invention.

FIG. 43 is a diagram for explaining a non-linear quantization processingof a conventional image coding apparatus.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Embodiment 1

Referring to FIG. 1(a), there is shown the construction of a videosignal recording apparatus of Embodiment 1, in which additionalinformation is replaced with added dummy signal.

An additional information generator 2101 is to generate additionalinformation. A video signal divider 1001 is to divide 422 digital videosignal consisting of luminance signal to chrominance signal ratio of4:2:2, into two 211 digital video signal consisting of that ratio of2:1:1, based on a specified division format. A video signal converter1002 is to add a specified dummy signal into luminance signal in theinput 211 digital video signal to convert it into 411 digital videosignal consisting of luminance signal to chrominance signal ratio of4:1:1. A high-efficiency coder 1003 is to create compressed data fromthe input 411 digital video signal by a specified high-efficiencycoding. A data replacement unit 2101 is to replace data at a specifiedposition in the compressed data with the data output from the additionalinformation generator 2101. An error correction coder 1004 is to add aspecified correction code data into the compressed data. A recordingapparatus 1005 is to record the output results from the error correctioncoder 1004 in a recording media 1006. Examples of the recording media1006 include a tape media such as VTRs, and a disk media such as opticaldisks, in which digitized data is recorded for retention.

The video signal recording apparatus so constructed will compress/codevideo signal and record it in the following operations.

The video signal divider 1001 discards input video signal of areas otherthan a significant area, i.e., a processing object. The input videosignal is 422 digital video signal having the aforesaid ratio of 4:2:2,which signal is then divided into two 211 digital video signals by thevideo signal divider 1001 based on a specified division format. These211 digital video signals are separately input to either of the videosignal converters 1002.

Each video signal converter 1002 adds a specified dummy signal to theluminance signal in the 211 digital video signal to convert it into 411digital video signal, and outputs it to each high-efficiency coder 1003.As described in prior art, the 211 digital video signal as shown in FIG.13(c), whose data is arranged in this order of luminance signal (Y),luminance signal (Y), chrominance signal (V) and chrominance signal (U),is converted into 411 digital video signal as shown in FIG. 13(d), whosedata is arranged in the order: luminance signal (Y), dummy signal (D),luminance signal (Y), dummy signal (D), chrominance signal (V) andchrominance signal (U), wherein every dummy signal (D) has the samedata.

The foregoing operations are common to those of the conventionalapparatus, while the additional information generator 2101 generates aspecified additional information and outputs it to the data replacementuntil 2102.

Each high-efficiency coder 1003 codes the respective input 411 digitalvideo signal at high efficiency utilizing a specified high-efficiencyalgorithm, to output compressed data. Referring to FIGS. 2(a) to 2(c),the format of the compressed data will be exemplified. The coder 1003inherently codes 411 digital video signal at high efficiency by thealgorithm utilizing DCT. The DCT block consists of 8×8 pixels. A set offour luminance signal (Y), one chrominance signal (V) and onechrominance signal (U) defines a macro block.

When used 411 digital video signal, the compressed data of such a macroblock is arranged as shown in FIG. 2(a). Each DCT block is arranged inthis order: DC composition, ancillary information data, and ACcomposition. When employed dummy signal, the DCT block is arranged asshown in FIG. 2(b). The block of the dummy signal (D) consists of aspecified DC composition, ancillary information data, and EOB (end ofblock), which are arranged in this order. The foregoing is common to aformat in prior art as shown in FIGS. 14(a) and 14(b).

The compressed signal having the constitution shown in FIG. 2(b) isoutput from each coder 1003 to each data replacement unit 2102. The unit2102 replaces the data at a specified area in the compressed data withthe additional information generated at the additional informationgenerator 2101, and outputs the resulting data.

A replacement method will be described referring to FIGS. 2(a) to 2(c).In each data replacement unit 2102, the DC composition in the dummysignal recording area, or the parts of the DC composition data and theancillary information data, is replaced with the additional information,to obtain the constitution as shown in FIG. 2(c), and the resulting datais output to each error correction coder 1004.

Each coder 1004 outputs error correction coded data which is obtained byadding a specified error correction code to the input compressed data.Each recording apparatus 1005 records the error correction coded data ina specified position of a specified recording media 1006.

As described above, the video signal recording apparatus of Embodiment 1is provided the additional information generator 2101 and the datareplacement unit 2102 in order to add and record the additionalinformation that can be created depending on the purpose, instead ofdummy signal to be recorded in a conventional video signal recordingapparatus. Therefore, more information can be recorded, permitting theeffective use of recording media.

Embodiment 2

Referring to FIG. 1(b), there is shown the construction of a videosignal recording apparatus of Embodiment 2, in which the additionalinformation to be created from the input video signal of areas otherthan a significant area is replaced with added dummy signal.

In the video signal divider 1001 the parts of significant area of 422digital video signal having the aforesaid ratio of 4:2:2 are dividedinto two 211 digital video signals based on a specified format, and theother parts are output to the additional information generator 2101. Inthe generator 2101 the input video signal (signals in areas other thanthe significant area) is temporally stored and additional information isgenerated from that signal. Others are common to Embodiment 1.

The operations of Embodiment 2 are common to those of Embodiment 1,except that the additional information is generated by the video signaldivider 1001 and the additional information generator 2101 as described.

In the video signal recording apparatus so constructed, the video signaldivider 1001 outputs the video data of areas other than the significantarea being a processing object, to the additional information generator2101. The generator 2101 generates additional information based on thevideo data from the divider 1001. The data replacement unit 2102replaces dummy information with the additional information. It istherefore possible to record more information than the conventionalrecording apparatus, and to utilize data of areas other than asignificant area, which data has been regarded as data beyond processingobject, and then discarded in the conventional apparatus. Hence, whentreating data containing parts to be cut off due to nonstandard video,and data accompanying such as control information and managementinformation, the apparatus of Embodiment 2 is able to utilize suchcut-off data and accompanying information data.

Embodiment 3

Referring to FIG. 3(a), there is shown the construction of a videosignal recording apparatus of Embodiment 3, which replaces added dummysignal with compressed/coded additional information. In ahigh-efficiency coder 2201 (for additional information), the additionalinformation generated in the additional information generator 2101 issubjected to a high-efficient coding utilizing a specifiedhigh-efficiency coding algorithm, to obtain compressed data, which datais then output. Others are common to FIG. 1(a), and the descriptions aresimilar to those of Embodiment 1.

The operations of Embodiment 3 is common to those of Embodiment 1,except that the coder 2201 codes the additional information generated inthe generator 2101 at high efficiency, utilizing a specifiedhigh-efficiency coding algorithm, and outputs the resulting data dscompressed data; and that the data replacement units 2102 replaces thedata at a specified area in the compressed data generated in thehigh-efficiency coders 1003 with the compressed data generated in thecoder 2201, and outputs it.

Thus in Embodiment 3, the additional information generator 2101 and thedata replacement unit 2102 enable to record more information than aconventional video recording apparatus. In addition, the high-efficiencycoder 2201 (for additional information) enables to compress additionalinformation. It is therefore possible to add more additional informationthan Embodiment 1, leading to further effective use of recording media.

Embodiment 4

Referring to FIG. 3(b), there is shown the construction of a videosignal recording apparatus of Embodiment 4, which replaces added dummysignal with additional information that is created from input videosignals of areas other than a significant area and thencompressed/coded.

The video signal divider 1001 and the additional information generator2101 are common to those of Embodiment 2. The divider 1001 outputs inputvideo signal of areas other than a significant area to the generator2101. The generator 2101 generates additional information from thereceived video signals. Others are common to FIG. 3(a), and thedescriptions are the same as those of Embodiment 3.

The operations of the apparatus of Embodiment 4 so constructed are thesame as those of Embodiment 3, except the operations of the divider 1001and the generator 2101 as described.

Thus in Embodiment 4, the video signal divider 1001 outputs the videodata of areas other than the significant area, i.e., a processingobject, to the additional information generator 2101. The generator 2101generates additional information based on the video data from thedivider 1001. The high-efficiency coder 2201 compresses the additionalinformation. The data replacement unit 2102 replaces dummy informationwith the compressed additional information. It is therefore possible torecord much information like Embodiment 3.

Furthermore when a video contains such as nonstandard parts andaccompanying information, Embodiment 4 can utilize such parts andinformation like Embodiment 2.

Embodiment 5

Referring to FIG. 4(a), there is shown the construction of a videosignal recording apparatus of Embodiment 5, in which at the conversionof video signal there is added additional information instead of dummyinformation.

A video signal converter 2301 adds additional information generated inan additional information generator 2101 to the luminance signal in theinput 211 digital video signal, to convert it into 411 digital videosignal. Others are common to FIG. 1(a) and 1(b), except that Embodiment5 is not provided with data replacement units (i.e., 2102).

The video signal recording apparatus so constructed will compress/codevideo signal and then record it in the following operations. LikeEmbodiment 1, the video signal divider 1001 divides 422 digital videosignal being input signal to obtain two 211 digital video signals, andthen outputs them to the video signal converters 2301. The additionalinformation generator 2101 generates a specified additional informationand then output it to the video signal converters 2301. The converter2301 adds the additional information generated in the generator 2101 tothe luminance signal in the 211 digital video signal, to convert it into411 digital video signal.

The conversion will be described using two examples, in both of whichthe digital video signal having the construction shown in FIG. 5(a) isconverted into that, shown in FIG. 5(b).

In the first example the data of 211 digital video signal is arranged inthis order: luminance signal (Y), luminance signal (Y), chrominancesignal (V) and chrominance signal (U). This data is converted into 411digital video signal arranged in this order: luminance signal (Y),additional information signal (S), luminance signal (Y), additionalinformation signal (T), chrominance signal (V), and chrominance signal(U). In this conversion, when no additional information signal isrequired, dummy signal (D) of identical data may be added like priorart. Thus such a conversion enables that additional information is addeddepending on the purpose.

The second example differs from the former in that additionalinformation signal is added when data is arranged as DCT blocks of 8×8pixels by the high-efficiency coder 1003, so as to have an identicalvalue in a single DCT block. In such a conversion, signal containing noAC component can be obtained from DC component alone, so that data to bereliably regenerated is recorded.

Thus in Embodiment 5, the additional information generator 2101 and thevideo signal converter 2301 in which the additional informationgenerated in the generator 2101 is added at the signal conversion,enable to record more information than the conventional signal recordingapparatus, like Embodiment 1 where firstly dummy signal is added andthereafter the dummy signal is replaced with additional information bythe data replacement unit.

Depending on the setting, it is possible that additional information isadded as required, and such dummy. signal as used in prior art may beadded unless any additional information is required. It is also possibleto add additional information to be reliably regenerated, with itscompression processing into consideration. There are hardly differencein effect between Embodiment 5 and Embodiment 1 having the datareplacement unit. Therefore, it is preferable to select eitherembodiment, depending on the components, circuit design of theapparatus; and data types and data quality and the like.

Embodiment 6

Referring to FIG. 4(b), there is shown the construction of a videosignal recording apparatus of Embodiment 6, in which at the video signalconversion there is added additional information created from inputvideo signal of areas other than a significant area, instead of dummyinformation.

The video signal divider 1001 and the additional information generator2101 are common to Embodiment 2. The divider 1001 outputs the inputvideo signal of areas other than the significant area to the generator2101 in which additional information is generated based on the receivedvideo signal. Others are common to FIG. 6(a), and the their descriptionsare the same as those of Embodiment 5.

The operations of Embodiment 6 are common to those of Embodiment 5except that the additional information is generated by the divider 1001and the generator 2101 as described.

Thus, Embodiment 6 that include no data replacement unit like Embodiment5 is able to record much information, and to utilize nonstandard partsand accompanying information if they are contained in video.

Embodiment 7

Referring to FIG. 6(a), there is shown the construction of a videosignal recording apparatus of Embodiment 7, in which at the video signalconversion there is added compressed/coded additional information,instead of dummy information.

A high-efficiency coder 2401 (for additional information) codes theadditional information generated by the additional informationgenerator, utilizing a specified high-efficiency coding algorithm, andthen outputs it as compressed data. A video signal converter 2402 addsthe compressed data from the coder 2401 to the luminance signal in theinput 211 digital video signal, to convert it into 411 digital videosignal. Others are common to FIG. 4(a), and the descriptions are thesame as those of Embodiment 5.

In Embodiment 7 so constructed, video signal is compressed/coded andthen recorded in the following operations.

The video signal divider 1001 divides the effective area of 422 digitalvideo signal, i.e., input signal, to obtain two 211 digital videosignals, and outputs it to the converter 2402. The additionalinformation generator 2101 generates a specified additional informationand then outputs it to the coder 2401. The coder 2401 efficiently codesthe additional information generated in the generator 2101 to obtaincompressed data, and then outputs it to the converter 2402. Theconverter 2402 adds the compressed data from the coder 2401 to theluminance signal in the 211 digital video signal, to convert it into 411digital video signal.

The aforesaid conversion will be discussed taking two examples, in bothof which the digital video signal having the construction shown in FIG.7(a) is converted into that shown in FIG. 7(b).

In the first example the data of 211 digital video signal is arranged inthis order: luminance signal (Y), luminance signal (Y), chrominancesignal (V) and chrominance signal (U). This data is converted into 411digital video signal of the sequence; luminance signal (Y), additionalinformation signal (S′), luminance signal (Y), additional informationsignal (T′), chrominance signal (V) and chrominance signal (U). In thisconversion, when no additional information signal is required, dummysignal (D) of identical data may be added like prior art. Thus such aconversion enables that additional information is added depending on thepurpose.

The second example differs from the former in that additionalinformation signal is added when data is arranged as DOT blocks of 8×8pixels in the high-efficiency coder 1003, so as to have an identicalvalue in a single DCT block. In such a conversion, a signal containingno AC component can be obtained from DC component alone, so that data tobe reliably regenerated is recorded.

Thus Embodiment 7 is provided with the additional information generator2101, the high-efficiency coder 2401 that compresses the additionalinformation generated by the additional information generator 2101, andthe video signal converters 2402 that adds the compressed data which isobtained by compressing/coding of the additional information, to thevideo signal. Hence, like Embodiment 3 where firstly dummy signal isadded and the dummy signal is replaced with the compressed additionalinformation by the data replacement unit, the use of the compressedinformation enables to record much more information than Embodiment 1 or5.

Like Embodiment 5, depending on the setting, it is possible thatadditional information is added if required, and such dummy signal asused in prior art is added unless any additional information isrequired. It is also possible to add additional information to bereliably regenerated, with its compression processing intoconsideration.

There are hardly difference in construction between Embodiment 3 andEmbodiment 7, like between Embodiments 1 and 5.

Embodiment 8

Referring to FIG. 6(b), there is shown the construction of a videosignal recording apparatus of Embodiment 8, in which at the video signalconversion there is added additional information created from inputvideo signal of areas other than a significant area, instead of dummyinformation.

The video signal divider 1001 and the additional information generator2101 are common to Embodiment 2. The divider 1001 outputs the videosignal of areas other than a significant area to the generator 2101 inwhich additional information is generated from the received videosignal. Others are common to FIG. 6(a), and the descriptions are thesame as those of Embodiment 7.

The operation of Embodiment 8 is the same as that of Embodiment 7 exceptthat the additional information is generated by the divider 1001 and thegenerator 2101 as described.

Thus, Embodiment 8 that includes no data replacement unit likeEmbodiment 7 can record much information and can utilize nonstandardparts and accompanying information if they are contained in video, likeEmbodiment 2.

Embodiment 9

Referring to FIG. 8(a), there is shown the construction of a videosignal recording apparatus of Embodiment 9, which replaces added dummysignal with additional information at the coding.

Like Embodiment 1, high-efficiency coders 2701 not only obtaincompressed data but also replace and insert additional information blockin the compressed data, the block consisting of additional informationand an EOB (end of block). An additional information generator 2101generates additional information and then outputs It to the coders 2701.Others are common to FIG. 1(a), except that the data replacement unit(i.e., 2102) is provided unlike Embodiment 1.

The video signal recording apparatus so constructed will compress/codevideo signal and record it in the following operation.

The operations of the video signal divider 1001 and the video signalconverter 1002 are the same as those of Embodiment 1.

The additional information generator 2101 generates additionalinformation and outputs it to the high-efficiency coders 2701. In thecoders 2701, 411 digital video signal from the converters 1002 is codedby a specified high-efficiency coding to obtain compressed data, andthen the block of dummy signal is replaced with additional informationblock in the compressed data, which block consisting of additionalinformation and an EOB.

An example of insert compression codes for additional information blockwill be described. FIG. 9(a) illustrates the construction of a macroblock of a conventional video signal recording apparatus, whichconstruction is the same as FIG. 14(a). FIG. 9(b) illustrates acompressed code to which additional information block has been inserted,wherein the blocks designated by “J” and “K” are the additionalinformation. As seen from the figure, the compressed code consists ofthe ancillary information data and EOB.

Thus in Embodiment 9, the additional information generator 2101generates additional information and outputs it to the high-efficiencycoders 2701, in which a block including EOB is made based on theadditional information and the block of dummy signal in the compresseddata is replaced with the obtained block. Therefore, like Embodiment 1where the dummy signal is replaced with the additional signal by thedata replacement unit, it is possible to record more information thanconventional video signal recording apparatuses. It is also possible toobtain data that can be regenerated by conventional video signalregenerating apparatuses.

It should be noted that in Embodiments 1, 3, 5, 7 and 9, additionalinformation can be created as information transmission function in imagedisplay, e.g. video to be added, telop and character information, ascontrol/management information, e.g., time code, and as informationcontaining no important content, e.g., background colors. That is,various additional information can be created properly.

Embodiment 10

Referring to FIG. 8(b), there is shown a video signal recordingapparatus of Embodiment 10, which replaces added dummy signal withadditional information created from the parts other these thesignificant area in input video signal, at the coding.

The video signal divider 1001 and the additional information creator2101 are common to those of Embodiment 2. The divider 1001 outputs partsother than the significant area in the input video signal to thegenerator 2101, in which additional information is generated from theinput video signal. Others are common to FIG. 8(a), and theirdescriptions are the same as those of Embodiment 9.

The operation of Embodiment 10 is the same as Embodiment 9, except thatthe additional information is created by the divider 1001 and thegenerator 2101 as described.

Thus, Embodiment 10 so constructed enables to record more informationthan the conventional video signal recording apparatus, like inEmbodiment 9, and to obtain data that is regenerative by theconventional video regenerating apparatus. Furthermore, similar toEmbodiment 2 it is able to utilize nonstandard parts and accompanyinginformation if they exist in video.

It should be noted that although in each of Embodiments 1 to 10 thereare shown the two recorders independently perform the recording to therecording media, in accordance with the apparatuses of prior art shownin FIG. 12(a), each Embodiment may carry out the recording via asynthesizer shown in FIG. 12(b), resulting in the same effect.

Embodiment 11

Referring to FIG. 10(a), there is shown the construction of a videosignal regenerating apparatus of Embodiment 11, in which compressed andcoded data including additional information is decoded and then theadditional information is split.

A video recording media 1006 is that to which the error correction codeddata has been recorded in the video signal recording apparatus ofEmbodiment 1. Regenerator 2001 regenerates (reads out) the errorcorrection coded data from the recording media 1006. An error correctiondecoder 2002 performs error corrections based on the error correctioncodes added by the video signal recording apparatus, and then outputsthe results as compressed data. A high-efficiency decoder 2003 performsthe reverse conversion of the high-efficiency coding performed by thevideo signal recording apparatus to decode digital video signal. A videosignal splitter 2501 splits the video signal in the significant area andthe additional information added by the video signal recording apparatusfrom the 411 digital video signal decoded in the decoder 2003, andoutputs the former as 211 digital video signal to a video signalsynthesizer 2005 and outputs the latter as it is to an additionalinformation synthesizer 2502. The synthesizer 2005 synthesizes the 211digital video signal from two video signal splitters 2004 based on aspecified synthetic format to output it as 422 digital video signal. Theadditional information synthesizer 2502 synthesizes the additionalinformation from the two splitters 2004 based on a specified syntheticformat to obtain necessary information.

The video signal regenerating apparatus so constructed will regeneratethe data recorded in the recording media in the following.

The regenerating apparatus 2001 regenerates (reads out) the errorcorrection coded data that is recorded at a specified area in therecording media 1006. The error the regenerated data based on the systemof adding error correction codes in the video signal recordingapparatus, to output the results as compressed data.

In the high-efficiency decoder 2003 the reverse conversion of thehigh-efficiency coding in the video signal recording apparatus iscarried out for the compressed data after the error corrections todecode digital video signal, thereby outputting it as 411 digital videosignal. The video signal splitter 2501 splits the 411 digital videosignal decoded in the decoder 2003 into the video signal of thesignificant area and the additional information added in the videosignal recording apparatus, and then outputs the former as 211 digitalvideo signal to the video signal synthesizer 2005 and outputs the latteras it is to the additional information synthesizer 2502.

The video signal synthesizer 2005 synthesizes the 211 digital videosignal from the two splitters 2501 based on a specified synthetic formatto obtain 422 digital video signal and then outputs it.

The synthesizer 2502 synthesizes the additional information from the twovideo signal splitters 2501 to obtain necessary information.

Thus in the regenerating apparatus of Embodiment 11 the two video signalsplitters 2501 outputs the additional information split from the videosignal and the output additional information is then synthesized in theadditional information synthesizer 2502. It is therefore able toregenerate the video signal recorded in the video signal recordingapparatus of Embodiment 1 or 3, and to utilize the additionalinformation. This enables to obtain further more information thanconventional regenerating apparatus in which dummy signal is to bediscarded.

As to additional information such as information on control andmanagement and character information, it is effective to firstly splitsuch information by the regenerating apparatus of Embodiment 11 and thenutilize it appropriately.

Although the recording media 1006 is to be recorded in the video signalrecording apparatus in Embodiment 1, it is possible to employ thatrecorded in Embodiment 2, 5 or 6, resulting in the same effect.

Embodiment 12

Referring to FIG. 10(b), there is shown the construction of a videosignal regenerating apparatus of Embodiment 12, in which compressed andcoded data including additional information is decoded and the decodeddata is then utilized.

An additional information synthesizer 2502 synthesizes additionalinformation as in Embodiment 10, and then outputs its result to a videosignal/additional information synthesizer 2503. A video signalsynthesizer 2005 synthesizes the input video signal and then outputs itsresult to the synthesizer 2503. In the synthesizer 2503 the synthesizedvideo signal and the synthesized additional information thus input aresynthesized. Others are common to FIG. 10(a), and the descriptions arethe same as those of Embodiment 11.

The operation of the video signal regenerating apparatus of Embodiment12 is the same as that of Embodiment 11, except the operations of theadditional information synthesizer 2502, the video signal synthesizer2005 and the video signal/additional information synthesizer 2503.

Thus in Embodiment 12, the synthesized results of both the additionalinformation synthesizer 2502 and the video signal synthesizer 2005 areoutput to the video signal/additional information synthesizer 2503,thereby obtaining video in which video signal and additional informationhave been synthesized. Therefore, when applied to the cases where in thevideo signal recording apparatus, additional information is created asvideo information or additional information is created from video signalother than those of the significant area, such additional informationcan be utilized effectively.

It is noted that the recording media 1006 may be that recorded in therecording apparatus of Embodiment 1, 2, 5 or 6, preferably embodiment 2or 6.

Embodiment 13

Referring to FIG. 11(b), there is shown the construction of a videosignal regenerating apparatus of Embodiment 13, in which compressed andcoded data including additional information is decoded and additionalinformation is split and then decoded.

The recording media 1006 is that which has been recorded in the videosignal recording apparatus of Embodiment 3. High-efficiency Decoders2003 (for additional information) performs the reverse conversion of aspecified high-efficiency coding for the compressed data of theadditional information output from the video signal splitter 2501,thereby decoding the additional information. Others are common to FIG.10(a), and the descriptions are the same those of Embodiment 11.

The operation of the video signal regenerating apparatus so constructedwill be described. The data recorded in the recording media isregenerated in the following manner. The processing up to the decodingin the high-efficiency decoder 2003 is the same as that of Embodiment11.

The video signal splitter 2501 splits the 411 digital video signaldecoded in the decoder 2003 into the video signal of the significantarea and the compressed data of the additional information added in thevideo signal recording apparatus. The former is output to the videosignal synthesizer 2005 as 211 digital video signal, and the latter isoutput to the high-efficiency decoders 2601 information as it is.

Thus in Embodiment 13, the decoder 2003 enables to regenerate thecompressed data including the additional information compressedrepeatedly that has been recorded in the video signal recordingapparatus of Embodiment 3. It is therefore possible to utilize moreadditional information than the regenerating apparatus of Embodiment 11or 12.

It is noted that although the recording media 1006 is that which hasbeen recorded in the recording apparatus of Embodiment 3, it may he thatof Embodiment 4, 7 or 8.

Embodiment 14

Referring to FIG. 11(b), there is shown the construction of a videosignal regenerating apparatus of Embodiment 14. As in Embodiment 12, theadditional information synthesizer 2502 synthesizes additionalinformation and outputs its result to the video signal/additionalinformation synthesizer 2503, and the video signal synthesizer 2005synthesizes the input video signal and outputs its result to thesynthesizer 2503. The synthesizer 2503 synthesizes the input synthesizedvideo signal and the synthesized additional information. Others arecommon to FIG. 16, and the descriptions is the same as those ofEmbodiment 13.

The operation of Embodiment 14 is the same as that of Embodiment 13except the operations of the additional information synthesizer 2502,the video signal synthesizer 2005 and the video signal/additionalinformation synthesizer 2503.

Thus in Embodiment 14, the synthesized results of both the additionalinformation synthesizer 2502 and the video signal synthesizer 2005 areoutput to the video signal/additional information synthesizer 2503,thereby obtaining video in which video signal and additional informationhave been synthesized. Therefore, the video signal regeneratingapparatus of Embodiment 14 provides the following advantages. Whenapplied to the cases where in the video signal recording apparatusadditional information is created as video information or additionalinformation is created from video signal other than that of thesignificant area, such additional information can be utilizedeffectively, like Embodiment 11. It is possible to regenerate additionalinformation as being repeatedly compressed, enabling to utilize muchmore additional information, like Embodiment 12.

As the recording media 1006 there can be employed any of those whichhave been recorded in Embodiment 3, 4, 7 or 8, preferably in Embodiment4 or 8.

It is noted that although Embodiments 11 to 14 are described such thattwo regenerating apparatus individually regenerate (read-out) fromrecording media, according to the construction shown in FIG. 15(a) as aconventional apparatus, these Embodiments may be in the systemcomprising the read-out in the regenerating apparatus 2001 and thesplitting and decoding in the splitter 2006 as shown in FIG. 15(b),resulting in the same effect.

It is noted that although Embodiments 1 to 14 are described as theapparatus, the processing providing the aforesaid effects can be servedas soft in general apparatuses such as personal computers andworkstations.

It is noted that the error correction coding or decoding in Embodiments1 to 14 may be omitted.

Embodiment 15

An image coding apparatus and an image decoding apparatus of Embodiment15 are those in which a quantization representative point is added to alinear quantizing unit having a linear quantization representative valueto realize a non-linear quantization unit performing quantization orreverse quantization.

Referring to FIG. 16, there is shown the construction of the imagecoding apparatus of Embodiment 15. A pixel value input unit 101 inputs apixel value having a dynamic range of d-bit. A linear quantization unitgenerator 102 generates a linear quantization unit having linearquantization representative points. A non-linear quantization unitgenerator 103 adds the quantization representative point to the vicinityof a predictive value to generate a non-linear quantization unit whosequantization width in the vicinity of the predictive value is smallerthan that of the linear quantization unit. A quantization unit 104quantizes an input pixel value using the non-linear quantization unit toobtain the quantization value of n-bit. An output unit 105 outputs thequantization value obtained in the quantization unit. A predictive valuegenerator 106 generates a predictive value for the input pixel valuefrom the peripheral pixels of the input pixel.

The operation of the image coding apparatus so constructed will bedescribed. For shortness' sake, assuming that the input pixel value isindicated by 8-bit (d) and the quantization value after being coded is6-bit (n) wherein n=6, k=d−n=2; and that in order to add quantizationrepresentative points, the upper limit number of the addition (m) is 5,which number is previously set.

In the predictive value generator 106, utilizing the peripheral pixelsof the input pixel, a predictive value of 8-bit is generated for thepixel value from the pixel value input unit 101, as a linear sumobtainable from the quantization value of the peripheral pixels. Basedon the predictive value thus generated, a quantization representativevalue for the input pixel value is set in the linear quantization unitgenerator 102 and the non-linear quantization unit generator 103.

Referring to FIGS. 17(a) to 17(d), there is shown an example of settingof quantization representative values, in which the predictive value isassumed to be 13.

The linear quantization unit generator 102 sets linear quantizationrepresentative values including the predictive value of 13 as aquantization representative value. The generator 102 is assumed togenerate 2^(n)−m linear quantization representative values withquantization width of 2^(k), wherein m is previously set as an upperbound value of the quantization representative point to be added in thepreceding processing. In this example, the quantization representativevalues are set with the quantization width of 4 (2²), positioning thepredictive value 13 in the center. As shown in FIG. 17(a), 1, 5, 9 and17, 21, 25, 29 are set near 13 in the shown range. The number of thequantization representative values set on the whole is 59 (2⁶−5) fromthe above setting (2^(n)−m).

The non-linear quantization unit generator 103 adds not more than mquantization representative points near the above predictive value toreduce the quantization width near the predictive value than that of thelinear quantization unit generator. In this example, 4 (4<m−5)quantization representative values are added in the range of two levelsaround the predictive value of 13. As a result, the quantization widthis set to 1 only around the predictive value. Other parts are set to 4as described. The number of the resulting quantization representativevalues sums up to 63 (<2⁶), whereby the quantization value after codingis indicated in 6-bit.

Subsequently the quantization value for the smallest quantizationrepresentative value is set to be −31, and the quantization value isallocated in order Or ascending, from the smallest quantizationrepresentative value. As shown in FIG. 17(c), the quantization value of−2 is allocated to the quantization representative value of 1, . . . ,and 9 is allocated to 29 in this manner. On the whole, the quantizationvalues of −31 to 31 are allocated in order of ascending.

The quantization unit 104 selects the nearest quantizationrepresentative value for an input pixel value to obtain its quantizationvalue, and outputs it to the output unit 105. As shown in FIG. 17(d),when a pixel value is 2, the quantization value is −2, when a pixelvalue is 14, the quantization value is 14, and the like.

As described above, in the image coding apparatus of Embodiment 15, thequantization representative values are set basically by the linearquantization processing, and the quantization representative values areadded only in the vicinity of a predictive value. Therefore in thequantization processing there can perform such an operation processingas employed in linear processing. Even non-linear quantization does notrequire ROM table and the like. In stead of processing the differencebetween an input pixel value and a predictive value, the input pixelvalue is directly quantized, and therefore, the quantizationrepresentative value (pixel value) is proportional to the quantizationvalue. Thus, since each quantization value itself contains the absolutelevel information, even when a predictive value is incorrect, errorpropagation is hardly caused. In the example illustrated in FIGS. 17(a)to 17(d), only four quantization representative values added to thevicinity of the predictive value, i.e., non-linear parts, are affected.

Referring to FIG. 18, there is shown a construction of the imagedecoding apparatus of Embodiment 15. A description will be given of theoperation when this apparatus decodes the data coded as described above.

A quantization value input unit 301 inputs a quantization value as theresult of coding. A reverse quantization unit 302 performs the reversequantization of an input quantization valve utilizing the non-linearquantization unit generated in the non-linear quantization unitgenerator 103. An output unit 303 outputs the result of decoding. Othersare common to the image coding apparatus.

The operation of the image decoding apparatus so constructed will bedescribed. When a quantization value as the result of coding is inputfrom the input unit 301, a predictive value generator 106 generates, asa linear sum, a predictive value for the quantization value by utilizingthe peripheral pixels of the input quantization value.

Similar to the image coding apparatus, based on tho predictive valuegenerated in the predictive value generator 106, a non-linearquantization unit whose quantization width is small only in the vicinityof the predictive value is generated in the linear quantization unitgenerator 102 and the non-linear quantization unit generator 103.Utilizing the quantization unit thus obtained, the reverse quantizationunit 302 performs the reverse quantization of the quantization valueinput from the quantization input unit 301, and then outputs the resultto the output unit 303.

Therefore, the image decoding apparatus of Embodiment 15 realizes thereverse quantization of non-linear quantization without ROM tables andthe like, as in the aforesaid coding apparatus. It is therefore able torealize a decoding circuit with a considerably small circuit.

Thus in the image coding apparatus and the image decoding apparatus ofEmbodiment 15, a predictive value for an input data based on theperipheral data is generated in the predictive value generator 106. Thelinear quantization unit generator 102 and the non-linear quantizationunit generator 103 provide that after a quantization representativepoint is set by linear processing, quantization representative valuesare added in the vicinity of the predictive value to obtain thenon-linear quantization unit generator whose quantization width is smallonly in the vicinity of the predictive value, thereby performing thequantization or the reverse quantization. Since Embodiment 15 isbasically executed in the operation processing utilized in linearquantization, there is required no ROM tables and the like. Required areonly a simple adder, subtracter and comparator. By reducing the circuitscale, it is able to reduce costs and electric power and to realizehigh-speed processing. In the quantization and the reverse quantization,the object of the processing is input values, not differences. Thereforeeven when the predictive value is incorrect, the above mentioned smallcircuit can minimize the error propagation without lowering thecompressive rate.

Embodiment 16

An image coding apparatus and an image decoding apparatus of Embodiment16 are those in which a quantization representative point is added to alinear quantizing unit to realize a non-linear quantization unit forobtaining quantization values, like in Embodiment 15. These apparatusesprevent a decrease in dynamic range by a shift function.

Referring to FIG. 19, there is shown the construction of the imagedecoding apparatus of Embodiment 16. A shift value generator 107generates a shift value according to a specified system. Others arecommon to FIG. 16, and the descriptions are the same as those ofEmbodiment 15.

The operation of the image coding apparatus so constructed will bedescribed. Similar to Embodiment 15, assuming that an input pixel valueis indicated in 8-bit (d) and the quantization value after the coding is6-bit (n), wherein n=6, k=d−n=2, and the addition upper bound numberm=5.

When a pixel value is input from the pixel value input unit 101, thepredictive value generator 106 generates a predictive value of 8-bit asa liner sum that is obtainable from the quantization values of theperipheral pixels. Based on the predictive value thus generated, theshift value generator 107 generates a shift value that is obtainedaccording to a specified system. Based on the shift predictive valuethat is obtained by subtracting the above shift value from the abovepredictive value, the linear quantization unit generator 102 and thenon-linear quantization unit generator 103 set quantizationrepresentative values for an shift input value that is obtained bysubtracting the above shift value from the input pixel value.

Referring to FIGS. 20(a) to 20(d), there are shown an example of thesetting of the quantization representative point in Embodiment 16.Embodiment 16 differs from Embodiment 15 in that the shift predictivevalue is used in place of the predictive value.

The quantization unit 104 selects the nearest quantizationrepresentative value of a shift input value, and outputs an allocatedquantization value to the output unit 105.

In the image coding apparatus of Embodiment 16, the quantizationrepresentative values are basically added only in the vicinity of theshift predictive value by linear quantization, like Embodiment 15. Evennon-linear quantization, there is required no ROM tables and the like.Further, since the input pixel value is shifted and its resulting valueis directly quantized, error propagation during predictive coding issatisfactorily prevented.

Referring to FIG. 21, there is shown the construction of the imagedecoding apparatus of Embodiment 16, in which the above coded data isdecoded. The shift value generator 107 is the same as that of the imagecoding apparatus. Others are common to FIG. 18.

A description will be given of the operation of the image decodingapparatus of Embodiment 16. When a quantization value, i.e., the resultof the coding, is input from the quantization value input unit 301, thepredictive value generator 106 generates, as a linear sum, a predictivevalue for the input quantization value by utilizing the peripheralpixels. Based on the predictive value, the shift value generator 107generates a shift value according to a specified system.

Similar to the image coding apparatus, the linear quantization unitgenerator 102 and the non-linear quantization unit generator 103 providea non-linear quantization unit whose quantization width is small only inthe vicinity of the predictive value. Utilizing the obtained non-linearquantization unit, the reverse quantization unit 302 performs thereverse quantization of the quantization value input from thequantization value input unit 301. To the value thus obtained, the shiftvalue is added, followed by decoding. Its result is output to the outputunit 303.

The image decoding apparatus of Embodiment 16 realizes, like Embodiment15, the reverse quantization of non-linear quantization without ROMtables and the like. It is therefore able to realize a decoding circuitwith a considerably small circuit.

Thus in the image coding and decoding apparatuses of Embodiment 16, thelinear quantization unit generator 102 and the non-linear quantizationunit generator 103 provide the non-linear quantization by operationprocessing. It is therefore possible to reduce the circuit scale. Thisenables to reduce costs and electric power and to satisfactorily preventthe error propagation during the predictive coding.

Embodiment 16 further provides the following advantage. Based on thepredictive value generated in the predictive value generator 106, theshift value generator 107 generates a shift value according to aspecified system. Whereas in generating a non-linear quantization unit,instead of such a predictive value, there is employed a shift predictivevalue that is obtained by subtracting a shift value from a predictivevalue, thereby avoiding the limit of the dynamic range.

Specifically, Embodiment 15 realizes the non-linear quantization with asmall circuit and can prevent the error propagation during thepredictive coding. In Embodiment 15, however, the maximum number of thelinear quantization representative points is obtained by reducing thenumber of the quantization representative points to be added from theoriginal setting number of 2^(k), furthermore, the setting is executedaround a predictive point. As a result, in a dynamic range, an areaexceeding the maximum quantization representative value and an areabelow the minimum quantization representative value are substantiallybeyond the object, whereby the dynamic range is restricted.

Whereas in Embodiment 16, the shift of a predictive value due to a shiftvalue allows to extend such a restricted dynamic range in the directionof the shift, leading to the recovery of the range. It is thereforepossible to provide dynamic range equivalent to that of the case inwhich linear quantization is mainly performed.

Embodiment 17

An image coding apparatus of Embodiment 17 is for obtaining a non-linearquantization value by a linear quantization value generator and anon-linear quantization value generator.

Referring to FIG. 22, there is shown the construction of the imagedecoding apparatus of Embodiment 17. A linear quantization valuegenerator 401 generates a linear quantization value by the divisionprocessing of input pixel value. The generator 401 determines an offsetvalue by the remainder of the division processing, and includes anoffset value adding means for adding the offset value to the input pixelvalue. A non-linear quantization value generator 402 generates anon-linear quantization value by correcting the above linearquantization value with the difference between the input pixel value anda predictive value. Others are common to FIG. 16, and the descriptionsare the same as those of Embodiment 15.

The image coding apparatus so constructed will operate as follows. Whena pixel value is input from a pixel value input unit 101, a predictivevalue generator 106 generates a predictive value of 8-bit utilizing theperipheral pixels of the input pixel, as a linear sum obtained from thequantization values of the peripheral pixels. The input pixel value fromthe input unit 101 is also input to the linear quantization valuegenerator 401, in which by the offset value adding means an offset valuedetermined by lower k-bit of the predictive value is added to the inputpixel value and then divided with 2^(k) to be converted into a linearquantization value. The “k” is obtained as the difference between thebit number of the dynamic range of the input pixel value and that of thequantization value to be output.

The linear quantization value is then input to the non-linearquantization value generator 402 to be corrected based on the differencevalue between the input pixel value and the predictive value, convertedinto a non-linear quantization value and then output from the outputunit 105.

A description will be given of the algorithm for image coding. Similarto Embodiment 15, assuming that the input pixel value is indicated by8-bit (d), and the quantization value after the coding is 6-bit (n)(n=6, k=d−n=2). As shown in FIGS. 23(a) to 23(d), when settingquantization representative values, to linear quantizationrepresentative values with quantization width of 4, there are set sixquantization representative values consisting of four quantizationrepresentative values with quantization width of 1, adjacent to apredictive value (i.e., 13 in FIGS. 23(a) to 23(d)), and twoquantization representative values with quantization width of 2.

Referring to FIG. 24, there is shown a flow chart of the algorithm ofthe image coding according to Embodiment 17. The quantization operationof the image coding apparatus will be described. In FIG. 24, P(t)denotes the predictive value generated at time t, I(t) denotes the inputpixel value generated at time t, Q(t) denotes the input pixel valuegenerated at time t, RO denotes an offset value and IQ denotes a linearquantization value. For the sake for simplicity, assuming that there isused a regenerated value of immediately before. The regenerative valuecan be obtained from the predictive value by executing the algorithm.

In step S1 in FIG. 24, the offset value adding means of the linearquantization value generator 401 determines an offset value from lower2-bit of the predictive value P(−1) obtained from the regenerated valueat the time immediately before. In step S2, the offset value is added tothe input pixel value by the offset value adding means, and the resultis divided by 2² in the linear quantization value generator 401, toobtain a linear quantization value.

From step S3, the correction is performed by the non-linear quantizationvalue generator 402. In step S3, the difference between the predictivevalue and the input pixel value is obtained. In step S4, the obtaineddifference is determined whether it is positive or negative. In step S5or S6, a correction value is obtained. Based on the results, acorrection value for the quantization value is operated in step S7, anda regenerative value is operated in step S8. In step S9 and S10, it isdetermined whether either value is adopted based on the difference valuepreviously obtained. As a result, either of steps S10, S12 and S13 isexecuted to obtain a quantization value.

As described above, the conversion of the input pixel value into thequantization value is completed. Also in step S10, S12 or S13, aregenerative value P(0) is obtained, and in stop S14, the regenerativevalue is then feedbacked so as to use as a predictive value. Then, theoperation for obtaining the next quantization value is repeated.

As can be seen from the above algorithm, the image coding apparatus ofEmbodiment 17 can be executed only by simple add-subtract and thecomparison. Although non-linear quantization is employed, there isrequired no complex circuit such as ROM tables. This algorithm providesthe value equivalent to the linear quantized input pixel value as aquantization value, so that the influence of error propagation hardlyoccurs.

Referring to FIG. 25, there is shown the construction of the imagedecoding apparatus of Embodiment 17. A linear regenerative valuegenerator 601 generate a linear quantization value for the inputquantization value. The generator 601 includes an offset value addingmeans in which an offset values is determined by the remainder of thedivision operation of a predictive value, and the offset value is addedto a linear regenerative value. A non-linear quantization regenerativevalue generator 602 performs a correction by the difference valuebetween an input quantization value and a predictive value linearquantization value. A predictive value quantization value generator 603performs a division operation of the predictive value to obtain apredictive linear quantization value. A quantization value input unit301, an output unit 303 and a predictive value generator 106 are commonto FIG. 18, and the descriptions is the same as those of Embodiment 15.

A description will be given of the operation of the image decodingapparatus of Embodiment 17.

The offset value adding means in the linear regenerative generator 601finds a specified offset value against lower k-bit of the predictivevalue of the predictive value generator 106. The generator 601 performsa multiplication operation of an input quantization value from thequantization value input unit 301 to obtain the value of 2^(k), and addsthe above offset value to the value 2^(k) to convert it into a linearquantization regenerative value, and outputs it to the non-linearquantization value generator 602.

The generator 602 divides the predictive value by 2^(k) to obtain apredictive linear quantization value, and outputs it to the non-linearquantization value generator 602. The generator 602 adds a correctionvalue generated from the difference value between the input quantizationvalue and the predictive linear quantization value to a linearquantization regenerative value or a predictive value, to obtain aquantization regenerative value, and then outputs it to the output unit303.

A description will be given of the algorithm for image decoding.Assuming that an input pixel value at the coding and a regenerativevalue are indicated in 8-bit (d), a regenerative value after thedecoding is indicated in 8-bit, and the quantization value after thecoding is indicated in 6-bit (n) (n=6, k=d−n=2). In setting quantizationrepresentative values, similar to the coding apparatus, six quantizationrepresentative values are added and then provided, as shown in FIG. 23.

Referring to FIG. 26, there is shown a flow chart of the algorithm forImage decoding in Embodiment 17. According to the flowchart, adescription will be given of the algorithm for non-linear quantizationvalue operation. Assuming that P(t) denotes a quantization regenerativevalue and a predictive value each being generated at time t, Q(t)denotes an input quantization value input at time t, RO denotes anoffset value, PQ denotes a predictive value linear quantization valueand IQ denotes a linear regenerative value. For the sake of simplicity,assuming that the regenerative value at immediately before is used as apredictive value.

In step S1, the offset value adding means in the linear regenerativevalue generator 601 sets an offset value by lower 2-bit of thepredictive value P(−1) obtained from the quantization regenerative valueof immediately before. In step S2, the predictive value is divided by 2²in the predictive value linear quantization value generator 603 toobtain a predictive value linear quantization value PQ.

From step S3, the correction is performed in the non-linear quantizationregenerative value generator 602. In step S3, a difference value betweenthe predictive value linear quantization value and the inputquantization value is obtained. In step S4, it is determined whether thedifference is positive or negative. In step S5 or S6, a correction valueis obtained. Based on the results, the operation of a correctionregenerative value is operated in step S7, and steps S8 and S10, basedon the obtained difference value, it is determined whether either valueshould be adopted. Step S9, S11 or S12 is executed to obtain aquantization regenerative value.

As described above, the processing for decoding the input quantizationvalue into the quantization regenerative value is executed. The obtainedquantization regenerative value is feedbacked in step S13, whereby theoperation for obtaining the next quantization regenerative value isrepeated.

Although the image decoding algorithm employs a non-linear quantization,there is required no ROM table for the reverse quantization. Requiredare only simple add-subtract. Therefore, irrespective of the suitablechange of the quantization representative value due to a predictivevalue, the decoding processing can be realized with a considerable smallcircuit. in the image coding apparatus of Embodiment 17, the predictivevalue against the input date is generated based on the peripheral datain the predictive value generator 106. The linear quantization valuegenerator 401 and the non-linear quantization value generator 402provide that after the quantization representative value is set by thelinear processing, and the quantization representative value is added tothe vicinity of the predictive value to perform a non-linearquantization whose quantization width is small only in the vicinity ofthe predictive value, thereby obtaining a quantization value. This isexecuted by the operation processing used basically in linearquantization. Hence, without ROM tables and the like, the apparatus canbe realized by a simple adder-subtracter. It is therefore possible toreduce the size of the circuit, leading to reduced cost end electricpower, permitting a high-speed processing.

In the image decoding apparatus of Embodiment 17, a linear quantizationregenerative value is obtained by the linear processing in the linearregenerative value generator 601, a predictive value linear quantizationvalue is obtained in the predictive value linear quantization valuegenerator 603 based on a predictive value generated in the predictivevalue generator 106. Based on the results, the correction is executed inthe non-linear quantization regenerative value generator 602 based onthe difference value between the input quantization value and thepredictive linear quantization value, to obtain a quantizationregenerative value. It is therefore possible to realize the reversequantization with a small circuit and to reduce costs and electricpower.

In the quantization and the reverse quantization there is processed aninput value not a difference. Even when the predictive value isincorrect, the error propagation can be minimize without reducing thecompressive rate. This enables to realize with such a small circuit asdescribed.

Embodiment 18

An image coding apparatus of Embodiment 18 is for obtaining aquantization representative value by the linear quantization valuegenerator and the non-linear quantization value generator, like inEmbodiment 17. The apparatus prevents a decrease in dynamic range by ashift function.

Referring to FIG. 27, there is shown the construction of the imagedecoding apparatus of Embodiment 18. A shift value generator 107generates a shift value according to a specified system. Others arecommon to FIG. 22, and the descriptions are the same as those ofEmbodiment 17.

The image coding apparatus so constructed will operate as follows. Whena pixel value is input from a pixel value input unit 101, a predictivevalue generator 106 generates a predictive value of 8-bit utilizing theperipheral pixels of the input pixel, as a linear sum obtained from thequantization values of the peripheral pixels. Based on the generatedpredictive value, the shift value generator 107 generates a shift valueby a specified system. While a shift input value obtained by subtractingthe shift value from the input pixel value from the pixel value inputunit 101, is input to a linear quantization value generator 401 and, bythe offset value adding means, there is added an offset value determinedby lower k-bit of the predictive value, and then divided by 2^(k) to beconverted into a linear quantization value. The “k” is obtained as thedifference between the bit number of the dynamic range of the inputpixel value and that of the quantization value to be output.

The linear quantization value is then input to the non-linearquantization value generator 402 to be corrected based on the differencevalue between the input pixel value and the predictive value, convertedinto a non-linear quantization value and then output from the outputunit 105.

A description will be given of the algorithm for image coding. Similarto Embodiment 17, assuming that the input pixel value is indicated by8-bit (d), and the quantization value after the coding is 6-bit (n)(n=6, k=d−n=2). When setting quantization representative values, likeEmbodiment 17, there are added six quantization representative valuesconsisting of four quantization representative values with quantizationwidth of 1, and two quantization representative values with quantizationwidth of 2. It is noted that the predictive value is employed instead ofthe shift predictive value.

Referring to FIG. 28, there is shown a flow chart of the algorithm ofthe image coding according to embodiment 18. The quantization operationof the image coding apparatus will be described. In FIG. 28, P(t)denotes the predictive value generated at time t, Sf is a shift valueobtained from the predictive value, I(t) denotes the input pixel valuegenerated at time t, Q(t) denotes the input quantization value generatedat time t, RO denotes an offset value and IQ denotes a linearquantization value. For the sake for simplicity, assuming that there isused a regenerative value of immediately before. The regenerative valuecan be obtained from the predictive value by executing the algorithm.

In step S1 in FIG. 28, the shift value generator 107 determines a shiftvalue Sf from upper 5-bit of the obtained predictive value P(−1)obtained from the regenerative value of immediately before. In step s2,a shift input value obtained by subtracting the shift value from theinput pixel value, and a shift predictive value obtained by subtractingthe shift value from the predictive value. In step S3, the offset valueadding means in the linear quantization value generator 401 sets anoffset value by lower 2-bit of the shift predictive value. In step S4,after the offset value is added to the shift input value in the offsetvalue adding means and the result is divided by 2² in the linearquantization value generator 401, to obtain a linear quantization value.

From step S5, the correction is performed by the non-linear quantizationvalue generator 402. In step S5, the difference between the predictivevalue and the input pixel value is obtained. In step S6, the obtaineddifference is determined whether it is positive or negative. In step S7or S8, a correction value is obtained. Based on the results, acorrection value for the quantization value is operated in steps S8 andS9, and a regenerative value is operated in step S10. In stops S11 andS13, it is determined whether either value is adopted based on thedifference value previously obtained. As a result, either of steps S12,S14 and S15 is executed to obtain a quantization value.

As described above, the conversion of the input pixel value into thequantization value is completed. Also in step S12, S14 or S15, aregenerative value P(0) to which the shift value has been added isobtained, and in step S16, the regenerative value is then feedbacked soas to use as a predictive value. Then, the operation for obtaining thenext quantization value is repeated.

As can be seen from the above algorithm, the image coding apparatus ofEmbodiment 18 can be executed only by simple add-subtract and thecomparison. Although non-linear quantization is employed, there isrequired no complex circuit such as ROM tables. This algorithm alsoprovides the value equivalent to the linear quantized input pixel valueas a quantization value, so that the influence of error propagationhardly occurs.

Referring to FIG. 29, there is shown the construction of the imagedecoding apparatus of Embodiment 18. A shift value generator 107generates a shift value by a specified system. Others are common to FIG.25, and the descriptions are the same as those of Embodiment 17.

A description will be given of the operation of the image decodingapparatus of Embodiment 18. The shift value generator 107 generatesshift value by a specified system, based on the predictive valuegenerated in the predictive value generator 106. The offset value addingmeans in the linear regenerative generator 601 finds a specified offsetvalue based on lower k-bit of the shift predictive value. The generator601 performs a multiplication operation of an input quantization valuefrom the quantization value input unit 301 to obtain the value of 2^(k),and adds the above offset value to the value 2^(k) to convert it into alinear quantization regenerative value, and outputs it to the non-linearquantization value generator 602.

The generator 602 divides the predictive value by 2^(k) to obtain apredictive linear quantization value, and outputs it to the non-linearquantization value generator 602, The generator 602 adds a correctionvalue generated from the difference value between the input quantizationvalue and the predictive linear quantization value to a linearquantization regenerative value or a predictive value, to obtain aquantization regenerative value, and then outputs it to the output unit303.

A description will be given of the algorithm for image decoding.Assuming that an input pixel value at the coding and a regenerativevalue are indicated in 8-bit (d), and a quantization value after thecoding is indicated in 6-bit (n) (n=6, k=d−n=2). In setting quantizationrepresentative values, six quantization representative values are addedto be arranged, as in the image coding apparatus.

Referring to FIG. 30, there is shown a flow chart of the algorithm forimage decoding in Embodiment 18. According to the flowchart, adescription will be given of the algorithm for non-linear quantizationvalue operation. Assuming that P(t) denotes a quantization regenerativevalue and a predictive value each being generated at time t, Q(t)denotes an input quantization value input at time t, RO denotes anoffset value, PQ denotes a predictive value linear quantization value,Sf denotes a shift value obtained from the predictive value and IQdenotes a linear regenerative value. For the sake of simplicity,assuming that the regenerative value at immediately before is used as apredictive value.

In step S1 in FIG. 30, the shift value generator 107 determines a shiftvalue Sf by upper 5-bit of the predictive value P(−1) obtained from theregenerative value at immediately before the time. In step S2, the shiftvalue is subtracted from the predictive value to obtain a shiftpredictive value. In step S3, the offset value adding means in thelinear regenerative value generator 601 determines an offset value bylower 2-bit of the predictive value P(−1) obtained from the quantizationregenerative value at immediately before the time. In step S4, the shiftpredictive value is divided by 2² in the predictive value linearquantization value generator 603 to obtain a predictive value linearquantization value PQ.

From step 55, the correction is carried out in the non-linearquantization regenerative value generator 602. In step S5, a differencevalue between the predictive value linear quantization value and theinput quantization value is obtained. In step S6, it is determinedwhether the difference value is positive or negative. In step S7 or S8,a correction value is obtained. Based on the results, a correctionregenerative value is operated in step S9. In steps S10 and S12, it isdetermined from the difference value whether either value should beadopted. Step S11, 13 or 14 is executed to obtain a quantizationregenerative value, a shift value is added thereto and the result isoutput.

Although the image decoding algorithm employs a non-linear quantization,there is required no ROM table for the reverse quantization. Requiredare only simple add-subtract. Therefore, irrespective of the suitablechange of the quantization representative value due to a predictivevalue, the decoding processing can be realized with a considerable smallcircuit.

In the image coding apparatus of Embodiment 18, the predictive valueagainst the input data is generated based on the peripheral data in thepredictive value generator 106. The linear quantization value generator401 and the non-linear quantization value generator 402 provide thatafter the quantization representative value is set by the linearprocessing, and the quantization representative value is added to thevicinity of the predictive value to perform a non-linear quantizationwhose quantization width is small only in the vicinity of the predictivevalue, thereby obtaining a quantization value. Thus, like Embodiment 17,the realization of the non-linear quantization processing at a smallcircuit allows to reduce costs and electric power. This permits ahigh-speed processing and enables to satisfactorily prevent the errorpropagation during the predictive coding.

In the image decoding apparatus of Embodiment 18, a linear quantizationregenerative value is obtained by the linear processing in the linearregenerative value generator 601, a predictive value linear quantizationvalue is obtained in the predictive value linear quantization valuegenerator 603 based on a predictive value generated in the predictivevalue generator 106. Based on the results, the correction is executed inthe non-linear quantization regenerative value generator 602 based on adifference value between the input quantization value and the predictivelinear quantization value, to obtain a quantization regenerative value.It is therefore possible to realize the reverse quantization with asmall circuit and to reduce costs and electric power.

Furthermore in the apparatus of Embodiment 18, based on a predictivevalue generated in the predictive value generator 106, the shift valuegenerator 107 generates a shift value by a specified system. Ingenerating a non-linear quantization unit, a shift predictive value thatis obtained by subtracting the shift value from the predictive value isemployed instead of the predictive value. Therefore, a dynamic rangerestricted by a decrease of a linear quantization representative valuecan be recovered by extending the range to the shift direction. Thisrealizes a dynamic range equivalent to that of the case in which linearquantization is mainly performed, like Embodiment 16.

It should be noted that although the correction for obtaining thenon-linear quantization value or non-linear quantization regenerativevalue is carried out based on the difference value between a shift inputvalue and a shift predictive value, it may be based on a differencevalue between a shift value and a predictive value, resulting in thesame effect.

Embodiment 19

An image coding apparatus and an image decoding apparatus of Embodiment19 are those in which quantization representative points are added to alinear quantizing unit to realize a non-linear quantization unit forobtaining a quantization value, and are provided with a function to setquantization representative points to a specific area.

Referring to FIG. 31, there is shown the construction of the imagedecoding apparatus of Embodiment 19. A non-linear quantization unitgenerator 701 generates a non-linear quantization unit in whichquantization representative points are added to a specific area inaddition to the vicinity of a predictive point. Others are common toFIG. 16, and the descriptions are the same as those of Embodiment 15.

The image coding apparatus so constructed will operate as follows.Similar to Embodiment 15, assuming that an input pixel value isindicated in 8-bit (d), a quantization value after the coding isindicated in 6-bit (n) wherein n=6, k=d−n=2; m=5 wherein a is the numberthat has been previously set for setting quantization representativevalues to be added; and p=3 wherein p is a second addition upper boundnumber that has been previously set for adding quantizationrepresentative points to a specific area.

The operations up to the linear quantization unit having linearquantization representative values is generated in the linearquantization unit generator 102, are common to Embodiment 15. The linearquantization representative values are generated with the quantizationwidth of 4 (2²), resulting in 59 (2⁶−5).

Referring to FIGS. 32(a), there is shown a setting of quantizationrepresentative values by the linear quantization unit generator 102. Inthis case, an area ranging from −128 to −119 and an area ranging from119 to 127 are beyond the area to be selected as quantizationrepresentative values.

The non-linear quantization unit generator 701 adds quantizationrepresentative values to linear quantization representative values. Thatis, not more than m−p quantization representative points are added inthe vicinity of the predictive value such that the quantization widthnear the predictive value becomes smaller than that of the linearquantization unit. In this example, in the range of two levels acrossthe predictive value of 13, two (m−p=2) quantization representativevalues, i.e., 11 and 15, are added as shown in FIG. 32(b). As a result,only in the vicinity of the predictive value, the quantization widthturns to be 2, while that of the other area is 4. The quantizationrepresentative points total 61.

Subsequently the non-linear quantization unit generator 701 adds eachone quantization representative value to the area ranging from −128 to−119 and the area ranging from 119 to 127 (2<p=3). The quantizationwidth of these area turns to be 8. As a result, the quantizationrepresentative values total 63 (<2⁶), whereby the quantization value asthe coding result is indicated by 6-bit.

As shown in FIG. 32(c), the quantization value allocated for the arearanging from −128 to −119 is −31 being the minimum. The quantizationrepresentative values are allocated in increasing order like Embodiment1, so that 31 is allocated for the area ranging from 119 to 127.

Subsequently the quantization in the quantization unit 104 and theoutput to the output unit 108 are carried out in the same manner as inEmbodiment 1.

Referring to FIG. 33, a description will be given of the image decodingapparatus of Embodiment 19 in which the above coded data is decoded.

A non-linear quantization unit generator 701 is the same as that of theimage coding apparatus. Others are common to FIG. 18.

The operation of the image decoding apparatus of Embodiment 19 is thesame as that of Embodiment 15, except that the quantizationrepresentative values of the non-linear quantization unit generated inthe non-linear quantization unit generator 701 are those which are shownin FIGS. 32(a) to 32(d).

There is required no ROM tableland the like, thereby realizing thedecoding processing at a small circuit.

As described above, the image coding and decoding apparatuses ofEmbodiment 19 are provided with the non-linear quantization unitgenerator that functions to add quantization representative values to aspecific area. Therefore, the dynamic range restriction due to theaddition of the quantization representative values to the vicinity of apredictive value, can be reduced by the construction having no functionof generating shift values in Embodiment 16.

Embodiment 20

An image coding apparatus and an image decoding apparatus of Embodiment20 are those in which non-linear quantization values are obtained by alinear quantization value generator and a non-linear quantization valuegenerator, and a specified coding or decoding is carried out in reply tothe input of a specific area.

Referring to FIG. 34, there is shown the construction of the imagedecoding apparatus of Embodiment 20. An input restriction unit 403examines the magnitude of an input pixel value from a pixel value inputunit. When it is within a specified range, the restriction unit 403outputs the input pixel value to a linear quantization value generator401, and, when it is beyond the range, does not output the input pixelvalue but outputs a specified quantization value to a non-linearquantization value generator 402. When the quantization value is outputfrom the restriction unit 403, the generator 402 outputs it to an outputunit 105. Others are common to FIG. 22, and the descriptions are thesame as those of Embodiment 17.

A description will be given of the operation of the image codingapparatus so constructed. Like Embodiment 17, assuming that an inputpixel value is indicated in 8-bit (d), a quantization value after thecoding is indicated in 6-bit (n) wherein n=6, k=d−n=2, the additionupper bound m is p5, and a second addition upper bound number p is 3.

When a pixel value is input from the pixel value input unit 101, thepredictive value generator 106 generates a predictive value of 8-bit byutilizing pixels around the input pixel. The input pixel value from theinput unit 101 is also input to the input value restriction unit 403 andthen determined whether it is within a specified range.

At that time, when the input pixel value is within the range, the inputpixel value is input to the linear quantization unit 401, and there isadded an offset value which is determined by lower k-bit of thepredictive value in the unit 401. Like in Embodiment 17, the obtainedvalue is converted into a linear quantization value by divisionprocessing, which value is then corrected in the non-linear quantizationvalue generator 402, based on a difference value between the input valueand the predictive value, so that it is converted into a non-linearquantization value and then output from the output unit 106.

On the other hand, when the input pixel value is outside of thespecified range, the input value restriction unit 403 generates anon-linear quantization value by a specified system, which value is theninput to the generator 402 and output from the output unit 105.

Referring to FIG. 36(a), when an input pixel value is in the range offrom −118 to 118, the input value restriction unit 403 outputs it to thelinear quantization value generator 401. The output pixel value is thenprocessed in the generator 401 and the non-linear quantization valuegenerator 402, like the coding apparatus of Embodiment 17, therebyobtaining a quantization value.

When an input pixel value is in the range of from −128 to −119, or from119 to 127, the restriction unit 403 does not output it to the generator401, but generates the non-linear quantization values “−31” or “31”, andoutputs it to the generator 402. This results in the same coding resultlike Embodiment 19.

Referring to FIG. 35, a description will be given of the image decodingapparatus of Embodiment 20 in which the above coded date is decoded.When a specific quantization value is input, a non-linear quantizationvalue generator 1201 outputs a specified regenerative value. Others arecommon to FIG. 25.

When a specific one is input to the quantization value input unit 301,the unit 301 outputs it to the non-linear quantization value generator1201, and the generator 1201 outputs a specified regenerative value tothe output unit 308. The above specific one is a specified non-linearquantization value that is output to the non-linear quantization valuegenerator 402 from the input value restriction unit 403. Other cases areprocessed in the same operation as in the image decoding apparatus ofEmbodiment 17.

Referring to FIG. 36(b), when the quantization value input to thequantization value input unit is neither −31nor 31, the same processingas in Embodiment 17 is executed to obtain a regenerative value, which isthen output, When it is −31 or 31, the non-linear quantizationregenerative value generator 1201 outputs −123 and 123, respectively, tothe output unit 308. This results in the same decoding result as inEmbodiment 19.

The image coding and decoding apparatuses of Embodiment 20 requires noROM table and the like, thereby realizing the coding/decoding processingat a small circuit. In addition, the apparatuses function to output aspecified value against the input pixel value or quantization value of aspecific area. Hence the dynamic range restriction due to the additionof quantization representative values to the vicinity of a predictivevalue, can be reduced by the construction having no function ofgenerating shift values in Embodiment 16.

Embodiment 21

The image coding apparatus of Embodiment 21 is provided with an inputrestriction function.

The image coding apparatus of Embodiment 15 realizes the non-linearquantization by adding quantization representative values to thevicinity of a predictive values of the quantization representativevalues obtained by linear quantization. The number of linearquantization representative values is reduced by the number ofquantization representative values to be added. Thus the range ofquantization in the linear quantization, i.e., dynamic range, should berestricted.

Referring to FIG. 37, there is shown the construction of the imagecoding apparatus of Embodiment 21. An input value restriction unit 403restricts he input value. An image coding unit 702 comprises the linearquantization unit generator, the non-linear quantization unit generator,the quantization unit and the predictive value generator as shown inEmbodiment 15. A pixel value input unit 101 and an output unit 105 arecommon to FIG. 16.

The image coding apparatus of Embodiment 21 performs the coding in thefollowing operations. The input pixel value from the pixel value inputunit 101 is input to the input value restriction unit 403, and thenrestricted to the range for which the quantization can be executed inthe linear quantization unit of the image coding unit 702. Therestricted input value is converted into a quantization value in thecoding unit 702, in the same coding processing as in Embodiment 15. Theobtained value is output to the output unit 105.

When m quantization representative points are added in the non-linearquantization unit, the restriction in the restriction unit 403 should beexecuted so that the dynamic range of the input pixel value is reducedby at least m×2^(k) levels.

As described above, in the image coding apparatus of Embodiment 21, theinput value restriction unit 403 restricts the input pixel values to therange capable of being processed by the linear quantization. It istherefore able to satisfactorily hold the characteristic that a fineimage quality is obtainable from the predictive coding in the non-linearquantization processing that prevents the error propagation due to asmall circuit.

It is noted that although the image coding unit 702 is constructedaccording to Embodiment 15, it may be constructed according toEmbodiment 17, resulting in the same effect.

Embodiment 22

The image coding apparatus of Embodiment 22 is provided with a functionto restrict a quantization value.

Referring to FIG. 38, there is shown the construction of the imagecoding apparatus. A quantization value restriction unit 801 restricts aquantization value. Others are common to FIG. 37.

The coding is carried out in the following. When an input pixel value isinput from the pixel value input unit 101, the coding unit 702 convertsthe input pixel value into a quantization value in the same codingprocessing as in Embodiment 15, and the obtained value is input to aquantization value restriction unit 801. The unit 801 detects the valueof the input quantization value and, when it is outside a range of fromthe minimum value to the maximum value determined to the quantizationvalue, the detective value is restricted to the range and than output tothe output unit 105.

Thus in Embodiment 22, the quantization value as the coding result isrestricted to a specific range by the quantization value restrictionunit 801, thereby omitting the restriction of the dynamic range of aninput value. This enables to obtain the same effect as in Embodiment 21.

It is noted that although the image coding unit 702 is constructedaccording to Embodiment 15, it may be constructed according toEmbodiment 17, resulting in the same effect.

Embodiment 23

The image coding apparatus of Embodiment 23 is provided with a functionto restrict shift input.

The construction of the apparatus is common to Embodiment 18, thedescription will be given referring to FIG. 27. The linear quantizationvalue generator 102 includes the shift input value restriction meansthat restricts the shift input value obtained from an input pixel valueand a shift value to a specific range. Others are common to Embodiment18.

Referring to FIG. 39, there is shown a flow chart illustrating thecoding algorithm of the image coding apparatus of Embodiment 23. Theflow of FIG. 39 differs from that of FIG. 28 in that the range of ashift input value is restricted in step S2. Others are common toEmbodiment 18.

Thus in Embodiment 23, the shift input restriction function provides theeffect similar to the input restriction function of Embodiment 21. Inthe apparatus of Embodiment 21, however, when input data is determinedas non-object by the fixed setting of the input restriction unit, suchinput data is never employed in the succeeding processing. Whereas inEmbodiment 23 the shift input restrictions realizes the restrictiondepending on the shift value setting, permitting a further flexibleapplication.

It is noted that although Embodiment 23 is constructed according toEmbodiment 18, it may be constructed according to Embodiment 16,resulting in the same effect.

Embodiment 24

The image coding and decoding apparatus of Embodiment 24 is able to seterror codes.

The construction of the image coding apparatus is same as that ofEmbodiment 22, and it will be described referring to FIG. 38. InEmbodiment 24 so constructed, a quantization value restriction unit 801enables to prohibit the use of a pattern of a specified n-bit in anormal quantization. This further enables to allocate an error codeshowing an error in a quantization value, to such a pattern not to beused. In a case where a quantization value is in 6-bit, the numeralsfrom −31 to 31 are utilized in the quantization, and −32 is set to anerror code.

Referring to FIG. 40, there is shown the construction of the imagedecoding apparatus of Embodiment 24 in which the error code processingis executed. An image decoding unit 901 comprises the linearquantization unit generator, the non-linear quantization unit generatorand the predictive value generator shown in FIG. 18, and the unit 901performs the same decoding processing as the image decoding apparatus ofEmbodiment 15. An error code detector 902 detects an error code of aninput quantization value. A predictive error setting unit 903 sets adifference from a predictive value.

A description will be given of the decoding processing in the decodingapparatus of Embodiment 24. An input quantization value from thequantization value input unit 301 is first determined whether it iserror code or not in the error code detector 902. For an error code, thedifference from a predictive value is set to be 0 in the image decodingunit 901 through the predictive error setting unit 903, therebyoutputting the predictive value as it is to the output unit 303. When aninput quantization value is not an error code, a normal decoding iscarried out in the decoding unit 901 and its result is output to theoutput unit 303.

In the above processing, when an error code is detected, the predictivevalue is output as a regenerative value.

When an error is contained in the data coded by the image codingapparatus so constructed, parts including such an error is replaced withan error code, whereby the above function of the decoding apparatus isvalid.

Referring to FIG. 41, there is shown a circuit for inserting an errorcode. A regenerative value input unit 9101 regenerates a coded data. Anerror code replacement unit 9102 replaces a quantization value of aregenerative data with an error code. An error detector 9103 detects anerror of a regenerative data. An output unit 9104 outputs data after thereplacement.

In the error code insertion circuit so constructed, the error detector9103 detects whether there is an error in data regenerated from amagnetic tape or a transmission signal in the input unit 9101. Thequantization value whose error is detected in the detector 9103 is thenreplaced with an error code in the error code replacement unit 9102. Inthis way, the quantization value that may have an error is replaced withan error code and than output to the output unit 9104.

Thus the image coding and decoding apparatuses of Embodiment 24 areprovided with the quantization value input unit 301, thereby setting aspecific quantization value as an error code. The obtained coded data issubjected to the error code replacement processing by the error codeinsertion circuit as described. Therefore, in the image decodingapparatus provided with the error code detector 902 and the predictiveerror setting unit 903, when an error code is detected, a predictivevalue itself is employed as a regenerative value, thereby minimizing theinfluence of the error.

Embodiment 25

It should be noted that the image coding and decoding apparatuses asdescribed in the foregoing have many common processing. In Embodiment25, therefore, there are shown a circuit common to these apparatuses.

Referring to FIG. 42, there is shown the construction common to thecoding apparatus and the decoding apparatus. A pixel value input unit1101, a quantization value input unit 1102, a quantization regenerativevalue output unit 1103 and a quantization value output unit 1104 arethose which are shown in FIG. 16 and FIG. 18 in Embodiment 15.

Numerals 1105 to 1112 designate switches, 1113 to 1123 designateadder-subtracters, 1124 and 1125 designate comparators, and 1126 and1127 designate delay units.

In the circuit shown in FIG. 42, at the quantization (decoding) theswitches 1105 to 1110 are connected in “e” direction, while at thereverse quantization (decoding) they are connected to “d” direction.Therefore at the coding, the same processing as the aforesaid imagecoding algorithm as previously described can be realized, and at thedecoding, the same processing as the aforesaid image decoding algorithmcan be realized.

Thus in the common circuit of Embodiment 25, the coding processing andthe decoding processing can be switched, permitting to share almost ofall circuits. This enables to considerably reduce the circuit size,leading to the reduced costs and effective applications of the deviceresource.

While the present invention has been described in terms of particularillustrative embodiments, many other modifications will occur to thoseskilled in the art without departing from the spirit and scope of theappended claims. The invention can comply with optional image signal. Asto the method of generating a predictive value, the bit numbers of aninput pixel value and a quantization value and the like, optionalmethods other than the embodiments are applicable. The constructionsillustrated in the embodiments can be realized in a variety of methodsand processing order, and also be realized by software. Additionally,the image coding apparatus and decoding apparatuses utilizing acombination of the above mentioned plural techniques are available.

What is claimed is:
 1. A video signal recording apparatus that considersdigital video signal to be input, said apparatus comprising: videosignal dividing means that divides said digital video signal to obtainvideo signal of a significant area; additional information generatingmeans for generating additional information; video signal convertingmeans for adding additional signal, said additional signal being a dummysignal, to the digital video signal of said significant area divided bysaid video signal dividing means; compression means that performs aspecified high-efficiency coding for the digital video signal to createcompressed video data; data replacement means for replacing data at aspecified position in said compressed video data with said additionalinformation generated by said additional information generating means;and means for recording the compressed data replaced by said datareplacement means in a specified recording media.
 2. A video signalrecording apparatus that considers digital video signal to be input,said apparatus comprising: video signal dividing means that divides saiddigital video signal to obtain video signal of a significant area;additional information generating means that temporarily stores areas tobe added other than said significant area of said digital video signal;video signal converting means for adding additional signal, saidadditional signal being a dummy signal, to the digital video signal ofsaid significant area divided by said video signal dividing means;compression means that performs a specified high-efficiency coding forthe digital video signal containing said additional signal to createcompressed video data; data replacement means for replacing data showinginformation of a dummy signal at a specified position in said compressedvideo data with the digital video signal temporarily stored in saidadditional information generating means; and means for recording thecompressed data obtained by said data replacement means in a specifiedrecording media.
 3. A video signal recording apparatus that considersdigital video signal to be input, said apparatus comprising: videosignal dividing means that divides said digital video signal to obtainvideo signal of a significant area; additional information generatingmeans for generating additional information; additional informationcompression means that performs a specified high-efficiency coding forsaid additional information generated by said additional informationgenerating means to create compressed video data; video signalconverting means for adding additional signal, said additional signalbeing a dummy signal, to the digital video signal of said significantarea divided by said video signal dividing means; compression means thatperforms a specified high-efficiency coding for the digital video signalcontaining said additional signal to create compressed video data; datareplacement means for replacing data, showing information of dummysignal, at a specified position in said compressed digital video datawith said compressed data compressed by said additional informationcompression means; and means for recording the compressed data subjectedto the replacement process by said data replacement means in a specifiedrecording media.
 4. A video signal recording apparatus that considersdigital video signal to be input, said apparatus comprising: videosignal dividing means that divides said digital video signal to obtainvideo signal of a significant area; additional information generatingmeans that temporarily stores areas to be added, other than saidsignificant area of said digital video signal; additional informationcompression means that performs a specified high-efficiency coding forthe digital video signal temporarily stored by said additionalinformation generating means to create compressed data; video signalconverting means for adding an additional signal, said signal being adummy signal, to the digital video signal of said significant areadivided by said video signal dividing means; compression means thatperforms a specified high-efficiency coding for the digital video signalcontaining said additional signal to create compressed video data; datareplacement means for replacing data showing information of the dummysignal at a specified position in said compressed digital video datawith said compressed data compressed by said additional informationcompression means; and means for recording the compressed data subjectedto the replacement process by said data replacement means in a specifiedrecording media.
 5. A video signal recording apparatus that considersdigital video signal to be input, said apparatus comprising: videosignal dividing means that divides said digital video signal to obtainvideo signal of a significant area; additional information generatingmeans for generating additional information; video signal convertingmeans for adding said additional information generated by saidadditional information generating means to a specified position of thedigital video signal of said significant area divided by said videosignal dividing means, to make all data in smallest coding unit of aspecified high-efficiency coding identical to one value among theadditional information; compression means that performs a specifiedhigh-efficiency coding for the digital video signal containing saidadditional signal to create compressed video data; and means forrecording the compressed data in a specified recording media.
 6. A videosignal recording apparatus that considers digital video signal to beinput, said apparatus comprising: video signal dividing means thatdivides said digital video signal to obtain video signal of asignificant area; additional information generating means for generatingadditional information; additional information compression means thatperforms a specified high-efficiency coding for said additionalinformation generated by said additional information generating means tocreate compressed additional data; video signal converting means foradding said additional information data generated by said additionalinformation compression means to a specified position of the digitalvideo signal of said significant area divided by said video signaldividing means, to make all data in smallest coding unit of a specifiedhigh-efficiency coding the same; compression means that performs aspecified high-efficiency coding for the digital video signal containingsaid compressed data to create compressed data; and means for recordingthe compressed data in a specified recording media.
 7. A video signalrecording apparatus that considers digital video signal to be input,said apparatus comprising: video signal dividing means that divides saiddigital video signal to obtain video signal of a significant area;additional information generating means that temporarily stores areas tobe added other than said significant area of said video signal;additional information compression means that performs a specifiedhigh-efficiency coding for the digital video signal temporarily storedby said additional information generating means to create compresseddata; video signal converting means for adding said compressed datagenerated by said additional information compression means to aspecified position of the digital video signal of said significant areadivided by said video signal dividing means, to make all data insmallest coding unit of a specified high-efficiency coding the same;compression means that performs a specified high-efficiency coding forthe digital video signal containing said compressed data to createcompressed data; and means for recording the compressed data in aspecified recording media.
 8. A video signal regenerating apparatus thatregenerates compressed data having additional information in a dummysignal recording area, said apparatus comprising: regenerating means forregenerating compressed data stored in a specified recording media;decoding means for decoding said compressed data, said decoding beingthe reverse conversion of a specified high-efficiency coding, to outputdigital video signal; video signal dividing means for dividing saiddigital video signal into a specified significant area and additionalinformation; and video signal synthesizing means for arranging digitalvideo signals of said significant area and additional area divided bysaid video signal dividing means in a specified order.
 9. A video signalregenerating apparatus that regenerates compressed data, havingadditional information in a dummy signal recording area said apparatuscomprising: regenerating means for regenerating compressed data storedin a specified recording media; decoding means for decoding saidcompressed data, said decoding being the reverse conversion of aspecified high-efficiency coding, to output digital video signal; videosignal dividing means for dividing said digital video signal intodigital signal of a specified significant area and digital signal ofadditional information; additional information decoding means fordecoding said digital signal of additional information divided by saidvideo signal dividing means, said decoding being the reverse conversionof a specified high-efficiency coding; video signal synthesizing meansfor arranging digital video signals of significant area divided by saidvideo signal dividing means in a specified order; and additionalinformation synthesizing means for recognizing additional informationdecoded by said additional information decoding means by a specifiedsystem.
 10. A video signal regenerating apparatus that regeneratescompressed data having additional information in a dummy signalrecording area, said apparatus comprising: regenerating means forregenerating compressed data stored in a specified recording media;decoding means for decoding said compressed data, said decoding beingthe reverse conversion of a specified high-efficiency coding, to outputdigital video signal; video signal dividing means for dividing saiddigital video signal of a specified significant area and digital signalof a specified additional information; video signal synthesizing meansfor arranging digital video signals of said significant area divided bysaid video signal dividing means and digital video signal output by saidadditional information decoding means in a specified order; andadditional area decoding means for decoding the digital signal of saidadditional area divided by said video signal dividing means, saiddecoding being the reverse conversion of a specified high-efficiencycoding to output a digital video signal.
 11. A video signal regeneratingapparatus that regenerates compressed data having additional informationin dummy signal recording area, said apparatus comprising: regeneratingmeans for regenerating compressed data stored in a specified recordingmedia; decoding means for decoding said compressed data, said decodingbeing the reverse conversion of a specified high-efficiency coding, tooutput digital video signal; video signal dividing means for dividingsaid digital video signal into a specified significant area andadditional information; video signal synthesizing means for arrangingvideo signals of said significant area divided by said video dividingmeans in specified order; and additional information synthesizing meansfor recognizing said additional information divided by said video signaldividing means by a specified system.
 12. A video signal recordingapparatus comprising: video signal dividing means that divides digitalvideo signal to obtain video signal of a significant area; additionalinformation generating means for generating additional information;compression means for creating compressed data by a specifiedhigh-efficiency coding, said coding being performed block by block, saidblock comprising a plurality of adjacent pixels, and replacingadditional information block composed of EOB (end of block) used in saidhigh-efficiency coding and said additional information with dummy signalrecording area in said compressed data; and means for recording thecompressed data in a specified recording media.